trunkmonkey55

Rcsnowb

If they do, don't use it! Buy a foam filter - less crap allowed into your motor.

K&N claims to filter out smaller particles then foam filters. I wouldn't know for sure as I don't have one but my buddies all ride the dunes and swear that they are better at filtering then foam filters. Yes K&N does make a filter for the WR but it's almost twice the price of the twin air.

SXP

K&N advertises freer flowing, doesn't clog, blah, blah, blah. This is my take on the K&N air filters:

Consider the following scenario: you with a K&N on your bike and your buddy with a foam filter on his bike, go out riding in a group. The ride is in dusty conditions, and on the average, both bikes are ridden in similar conditions - midpack, back of the pack, leading etc. At the end of the day your buddys bike runs like crap 'cause it's filter is clogged, but your bike still runs fine with the K&N even though it's dirty. Why's that? Both bikes were run in similar conditions. A similar amount of dirty air is presented to both filters, yet one clogs and the other still runs. I believe the foam filter stops the dirt right there and slowly clogs in the process, whereas the K&N, while still filtering dirt, allows a good amount of it thru to the engine.

That's my story and I'm sticking to it. I have the results of a test (long) that was conducted on different types of filters. Bottom line, the gauze/oil filters (K&N) are the worst performers with respect to small particle filteration. If you are interested, PM me and I'll email it to you (if I can find it).

YZDAD1

Yeah, what are those K&N folks thinking? All the engineering, marketing and investment dollars (probably hundreds of thousands) in a dirt bike line of filters! We're all so much smarter than them, they'll go broke, they'll put themselves out of business!!! LOL, let's set back and watch...............

SXP

Curious what your take on the clogging issue is? Why don't K&N's clog as fast as foam? I ran a K&N on my KLX650 for a while and noticed I could go a whole lot longer between cleaning as compared to a foam filter. That started bothering me and got me thinking. Then I read the results of an air filter test putting the oiled cotton gauze filters (K&N) dead last in small particle filteration and that was the clincher for me.

wildo

I agree w/ every one. Its not worth the mony. We put one it my buddy 250 ex quad and his intake valve was tost 6 mo. later. Of course this guys not much on matenenc. he propably never botherd to cleen and re oil the thing.

Indy_WR450

YZDAD1

1: foam oil filled filter surface area is exactly what you see, no folds or pleats. Only so many square inches of area.

2. K & N filter is a "folded & pleated" filter element that fits within the same air box area. That said, now unfold the filter and lay it out next to your foam filter and calculate the "square area" difference, considerable isn't it? (maybe the reason foam clogges first? )

3. Air filters like oil filters : tests and advertisements "educating" us on how many more microns or particulates that one brand over another filters or let through are just decision makers for the rest of us. Bottom line, any of the filters available will do a fine job, if however you elect not to service/clean them, they will all let you down eventually.

gfergtr74

I have used one in every vehicle I have ever owned. This being my first thumper I thought why not. In the past on my pickups the filter would clog in the pleats but the top would still be clean. I think that is why they last longer. However with all the talk about these lately I think I will be doing a little more research. I would rather lose the .25 horse power I gained with it than lose a motor.